The invention relates to a crane vehicle having a carrier and a rotating deck pivotable around a vertical axis thereon on which a boom swivellable around a horizontal axis is supported and at whose projecting, outer end pallets are mounted at both sides to receive counterweight slabs stacked on top of one another. In this crane vehicle, the projecting outer end of the rotating deck forms a counter-boom, so to speak, at which the counterweight is mounted to balance the boom and the load suspended thereon. If a larger counterweight is required to balance the boom and the load carried thereby, further counterweight slabs are normally placed on the stacked counterweight slabs. This is, however, relatively expensive because the additional counterweight slabs have to be transported and kept available.
It is therefore the object of the invention to produce a greater balancing counter-moment in a crane vehicle of the kind first mentioned without placing on additional counterweight slabs.
This object is solved in accordance with the invention by a frame being attachable to the outer end of the rotating deck, said frame being provided with accommodations or couplings at least for the respective rear suspension points of the pallets.
In the crane vehicle in accordance with the invention, the balancing moment is increased by the lever arm, at which the counterweight acts, being extended. This is achieved by the pallets supporting the stacked counterweight slabs being offset to the rear with respect to the rotating deck.
The frame extending the rotating deck to the rear can accept in each case one suspension point of the pallets or, however, also all suspension points of the pallets.
The suspension points can consist of bolt connections or hook connections.
A simple attachment of the pallets extending the lever arm is possible by the pallets being connectable by suspension devices situated at their side parts to counter-accommodations of the rotating deck and by the inner suspension devices of the pallets being able to be coupled to the outer counter-accommodations when the frame is attached. The inner suspension points of the pallets can in this way be coupled to the already present end counter-accommodations of the rotating deck so that the attached frame then only has to be provided with counter-accommodations for the outer suspension points of the pallets.
It is provided in accordance with another embodiment that the frame is provided with two accommodations or couplings for in each case two side suspension points of the pallet.
The suspension points can consist of bolt connections or hook connections.
The pallets are appropriately able to be coupled in the same manner to both the rotating deck and the frame which can be attached thereto. The pallets are therefore able to be coupled to counter-accommodations of the rotating deck by bolt or hook connections located at the side parts of said pallets, with the inner bolts or hook connections of the pallets being able to be coupled to the outer counter-accommodations of the rotating deck when the frame is attached.
It is provided in accordance with another aspect that the two pallets are connected to one another by a central intermediate piece connectable to the frame. In this embodiment, the side pallets are connected by the central intermediate piece to form a continuous slab or carrier, so to speak, whose central region is connected to the frame so that the parts of the carrier projecting over the frame at the side form the pallet-like accommodations for the counterweight slabs.
It can be appropriate in certain operating states to design the value of the stabilizing counter-moment variably. In accordance with another embodiment, it is therefore provided for the counterweight slabs to be displaceable with the positioned counterweight slabs on guides of the rotating deck. The lever arm, at which the counterweight acts, can therefore be adjusted to the different load cases by a corresponding displacement of the trolleys or slides bearing the counterweight slabs, for example by hydraulic cylinders.